Meiosis

Meiosis is the formation of gametes. The (unfertilized) egg and the sprem cell are the gamets.

Remember that birds are diploid: all chromosomes come in pairs (except maybe for XY in hens). The gametes only contain one of the two chromomes from the pair.

So, imagine this hen (2 chromosome pairs: AA and XY):
A A'
X Y

The gametes it will form are:

• A
  X
• A
  Y
• A'
  X
• A'
  Y

If you want to see the full process, click here